Production of textile articles

ABSTRACT

A process for adhering a foam backing to textile articles by applying a foamable composition of a vinyl chloride polymer, a plasticizer and a nitrogen-evolving blowing system which is active at a temperature below 150* C. to textile articles and thereafter applying heat to the treated article.

United States Patent 1 1 11 1 3,717,526 Visnovsky et al. 1 1 Feb. 20, 1973 541 PRODUCTION OF TEXTILE ARTICLES 3,032,828 5/1962 1mmcl ul v.156 711 x 2,962,407 ll 1960 A k I 1 lflvcnlorsl Lflbomir Visnovskyr Waterloo; 3,239,365 3/1966 m i Pierre Slordeur, Melle, both of 2,703,775 3/1955 Panagrossi et al ..l56/78 Belgium [73] Assignee: Monsanto-Europe S.A., Brussels,

Belgium Primary Examiner-Stephen J. Lechert, Jr. Att0rney-Neal E. Willis, John E. Maurer and Robert [22] Filed: May 18, 1970 wexler [2i] Appl. No.: 38,505

[30] Foreign Application Priority Data [57] ABSTRACT May 19. 1969 Great Britain ..25368/69 A Process for adhfling a foam backing to textile articles by applying a foamable composition of a vinyl [52] US. Cl. ..l56/78, 156/244, 156/306 Chloride p y r, a p asticizer and a nitrogen-evolving [51] Int. Cl. ..B32b 5/18 blowing system which is active at a temperature below [58] Field of Search ..l5 6/78, 79, 242, 244, 306; 150 C. to textile articles and thereafter applying heat 161/160 to the treated article.

[56] References Cited 21 Claims, N0 Drawings UNITED STATES PATENTS 2,943,949 7/1960 Petty ..l56/78 PRODUCTION OF TEXTILE ARTICLES BACKGROUND OF THE INVENTION This invention relates to the production of textile articles backed with a foamed resin.

It has been found that conventional blowing systems used in the process of foaming of vinyl chloride polymers do not work satisfactorily at lower temperatures. This is a considerable disadvantage when it is wished to apply the foam to articles which are not resistant to elevated temperatures. For this reason a process for applying to an article a foam which is fusible at a relatively low temperature is especially useful.

SUMMARY OF THE INVENTION Accordingly the process of the invention is one for producing a textile article backed with vinyl chloride polymer foam fusible at a temperature of below 150 C., which comprises applying to the textile article a foamable composition comprising polyvinyl chloride or a copolymer of vinyl chloride and a minor proportion of comonomer, a plasticizer, and a nitrogen-evolving blowing system active at a temperature below 150 C., and heating the treated article to activate the blowing system.

The process is particularly useful for backing carpets, and also flooring material, which contain synthetic fibers sensitive to or damaged by high temperatures (such as 150 C. or above), such as for example, nylon, acrylic, olefin, e.g., polypropylene, polyester or viscose fibers. Carpets and other textile materials which can be backed by foamed vinyl chloride polymer according to the process of the invention need not, of course, consist wholly of synthetic fiber but can include other materials that in themselves are heat resistant. The vinyl chloride polymer foam gives good adhesion to synthetic fibers, and because the process is operated below 150 C. there is little tendency for the synthetic fibers to deteriorate as a result of being overheated.

DESCRIPTION OF THE PREFERRED EMBODIMENTS In the process for producing a textile article backed with a vinyl chloride polymer foam the foamable composition can be applied to the textile article in paste form by spreading on to synthetic woven or non-woven articles, the paste being subsequently foamed. Also a textile article can be backed with the polymer foam by fusing a sheet of the foamed polymer on to the back of the article.

The invention further provides a textile article backed with a foamed polyvinyl chloride or a foamed copolymer of vinyl chloride and a minor proportion of comonomer, the foamed polymer being fusible at a temperature below 150 C. Preferably the textile article is a carpet containing synthetic fibers sensitive to or damaged by high temperatures.

The vinyl chloride polymers which are most useful are polyvinyl chloride and copolymers of vinyl chloride and a minor proportion of comonomer which is generally from 2 to 14 percent by weight and preferably from 2 to percent by weight of the copolymer. Excellent results are obtained when the proportion of comonomer is from 2 to 5 percent by weight of the copolymer. Convenient vinyl chloride copolymers which are used in accordance with this invention include copolymers of vinyl chloride with such comonomers as vinylidene halides such as vinylidene chloride, vinyl ethers such as acetyl vinyl ether and tridecyl vinyl ether, olefins such as ethylene and propylene, vinyl esters such as vinyl acetate, vinyl stearate and vinyl propionate and the like. The copolymers should preferably be paste forming resins and they can also contain a third copolymerizable monomer.

The vinyl chloride polymer foams used in the process of the invention are fusible at a temperature of below 150 C. Usually the temperature of fusion of the foam is within the range to C. and in the process foaming takes place at a corresponding temperature, the extent of the expansion being from 100 to 500 percent.

It is preferred to use a solvating type of plasticizer which gives low plastisol viscosity and slow ageing. Examples of suitable plasticizers include butylbenzylphthalate, dihexyl, diheptyl and dioctyl phthalate.

The nitrogen-evolving blowing systems generally comprise a mixture of conventional blowing agents and a metallic salt acting as a modifying agent or kicker. Conventional blowing agents which are used in accordance with this invention are azodicarbonamide, p,p'-oxybisbenzenesulfonyl hydrazide, benzenesulphonhydrazide and toluene sulfonhydrazide, among others. The blowing agents are used as mixtures such as a mixture of azodicarbonamide with benzenesulphonhydrazide or toluene sulphonhydrazide or a mixture of p,p'-oxybisbenzenesulfonyl hydrazide with benzenesulphonhydrazide or toluene sulphonhydrazide. The most preferred blowing system comprises a mixture of azodicarbonamide and benzenesulphonhydrazide, the benzenesulphonhydrazide being in a proportion of between 5 and 50 percent by weight of the azodicarbonamide and preferably between 10 and 40 percent by weight of the azodicarbonamide.

A particularly useful blowing system is that in which azodicarbonamide and benzenesulphonhydrazide are present in a proportion by weight of about 7 parts to 3 parts.

The best results are obtained when the finest particle size of azodicarbonamide is employed and the particles have a high specific area. Thus the surface area of the particles is preferably greater than 3.8 square meters per gram and the particle size is below 10 microns.

The operating temperatures of the process of the invention is modified by the presence of the metallic salt in the blowing agent. Specific examples of metals whose salts are useful include cadmium, zinc, barium and lead. Mixtures of these salts can also be used and the particularly preferred mixtures are of cadmium and zinc salts or barium and zinc salts. However, the most preferred salts are lead salts, in particular lead oleates.

It is found that the blowing system is preferably used in a ground paste form. When ground with normal PVC plasticizers the blowing system tends to decompose at room temperature and this difficulty is overcome if plasticizers such as epoxidized soya bean oil are incorporated into the blowing system.

The invention is illustrated by the following examples:

EXAMPLE 1 This example illustrates a process according to the invention for the production of a carpet containing acrylic fibers backed with a vinyl chloride copolymer foam.

A foamable composition comprising a copolymer of vinyl acetate and vinyl chloride containing percent by weight of vinyl acetate, was first prepared by adding to 100 parts by weight of the copolymer a paste comprising 65 parts by weight of a plasticizer and 6 parts by weight of a nitrogen-evolving blowing system. The plasticizer used was butylbenzylphthalate and the blowing system was a mixture of 3 parts azodicarbonamide, 1 part benzene-sulphonhydraz'ide and 2 parts liquid lead kicker.

The foamable composition was then fed into the hopper of a screw extruder and extruded through a slit die maintained at a temperature of 145 C. on to the back of a synthetic carpet containing acrylic fibers.

On examination it was found that the foam had adhered to the carpet and there had been no deterioration of the acrylic fibers.

EXAMPLE 2 This example illustrates a process according to the invention for the production of a carpet containing polypropylene fibers backed with a vinyl chloride copolymer foam.

A foamable composition comprising a copolymer of vinyl acetate and vinyl chloride containing 3 percent by weight of vinyl acetate, was first prepared by adding to 100 parts by weight of the copolymer a paste comprising 65 parts by weight of a plasticizer and 6 parts by weight of a nitrogen-evolving blowing system. The plasticizer used was a mixture of 40 parts of butylbenzyl-phthalate and 25 parts of dioctylphthalate, and the blowing system comprises 2.5 parts of azodicarbonamide, 1.5 parts of benzenesulphonhydrazide and 2 parts of liquid lead kicker.

The foamable composition was then fed into the hopper of a screw extruder and extruded through a slit die maintained at a temperature of 145 C. on to the back of a synthetic carpet containing polypropylene fibers.

On examination it was found that the foam had adhered to the carpet and there had been no deterioration of the propylene fibers.

EXAMPLE 3 This example illustrates a process according to the invention for the production of a carpet backed with a vinyl chloride copolymer foam.

The foamable composition described in Example 1 was made into a paste. A layer of the composition 1 millimeter thick, representing a coating weight of 1,250 grams per square meter, was spread on to a synthetic carpet containing propylene fibers.

The treated carpet was then heated in an air circulated oven at a temperature of 145 C. for a period of 12 minutes and a foam expansion of 350 percent was achieved.

On examination it was found that the foam had adhered to the carpet and there had been no deterioration of the polypropylene fibers.

EXAMPLE 4 This example illustrates a process according to the invention for the production of a carpet backed with a vinyl chloride copolymer foam.

The foamable composition described in Example 2 was made into a paste. A layer of the composition 1 millimeter thick, representing a coating weight of 1,250 grams per square meter, was spread on to a synthetic carpet containing nylon fibers.

The treated carpet was then heated in an air circulated oven at a temperature of C. for a period of 12 minutes and a foam expansion of 350 percent was obtained.

On examination it was found that the foam had adhered to the carpet and there had been no deterioration of the nylon fibers.

While theinvention has been described hereinabove with regard to certain illustrative embodiments, it is not so limited since many modifications and variations are possible in the light of the above teachings. It is understood therefore that the invention may be practiced otherwise than as specifically described without departing from the spirit and scope of the invention.

We claim:

1. A process for producing a textile article backed with vinyl chloride polymer foam fusible at a temperature below about C. which comprises applying to the textile article a foamable composition comprising a vinyl chloride polymer, a plasticizer and a nitrogenevolving blowing system active at a temperature below about 150 C. and heating the treated article.

2. A process according to claim 1 in which the textile article is a carpet.

3. A process according to claim 1 in which the textile article is a flooring material.

4. A process according to claim 1 in which the textile article contains fibers sensitive to or damaged by temperatures above about 150 C.

5. A process according to claim 4 in which the article contains nylon, acrylic, olefin, polyester or viscose fibers.

6. A process according to claim 1 in which the foamable composition is applied to the article in paste form by spreading said composition on a woven or nonwoven article, the paste being subsequently foamed.

7. A process according to claim 1 in which the vinyl chloride polymer is selected from the group consisting of polyvinyl-chloride and copolymers of vinyl chloride with vinylidene chloride, vinyl acetate, vinyl stearate, vinyl propionate, acetyl vinyl ether, tridecyl vinyl ether, ethylene and propylene.

8. A process according to claim 7 in which said comonomer is present in a minor proportion based on the weight of the copolymer.

9. A process according to claim 8 in which said comonomer is present in an amount of from 2 to 10 percent based on the weight of the copolymer.

10. A process according to claim 8 in which said comonomer is present in an amount of from 2 to 5 percent based on the weight of the copolymer.

11. A process according to claim 1 in which said blowing system is composed of nitrogen-evolving blowin g agents.

12. A process according to claim I] in which said blowing system is selected from the group consisting of a mixture of azodicarbonamide with bcnzencsulphonhydrazide or toluencsulphonhydrazide or a mixture of p,p'-oxybisbenzenesulfonylhydrazide with benzenesulphonhydrazide or toluenesulphonhydrazide.

13 A process according to claim 12 in which said mixture contains from about to about 40 percent by weight of the mixture of azodicarbonamide.

14. A process according to claim 1 in which said copolymer is fusible at a temperature of from about 135 C. to 150C.

15. A process according to claim 1 in which said plasticizer is selected from the group consisting of butylbenzylphthalate, dihexyl phthalate, diheptyl phthalate or dioctyl phthalate.

16. A process according to claim 1 in which said composition contains a metallic salt or mixtures of metallic salts.

17. A process according to claim 16 in which said metallic salt is a lead salt.

18. A process according to claim 17 in which said lead salt is a lead oleate.

[9. A process for producing a textile article backed with vinyl chloride polymer foam fusible at a temperature below about C. which comprises forming a sheet of foamed vinyl chloride polymer from a foamable composition comprising a vinyl chloride polymer, a plasticizer and a nitrogen-evolving blowing system active at a temperature below about 150 C. and fusing said sheet to said article.

20. A process according to claim 19 in which said article is a carpet.

21. A process according to claim 19 in which said sheet is fused to said article by directly applying a foaming layer of the foamable composition to said article. 

1. A process for producing a textile article backed with vinyl chloride polymer foam fusible at a temperature below about 150* C. which comprises applying to the textile article a foamable composition comprising a vinyl chloride polymer, a plasticizer and a nitrogen-evolving blowing system active at a temperature below about 150* C. and heating the treated article.
 2. A process according to claim 1 in which the textile article is a carpet.
 3. A process according to claiM 1 in which the textile article is a flooring material.
 4. A process according to claim 1 in which the textile article contains fibers sensitive to or damaged by temperatures above about 150* C.
 5. A process according to claim 4 in which the article contains nylon, acrylic, olefin, polyester or viscose fibers.
 6. A process according to claim 1 in which the foamable composition is applied to the article in paste form by spreading said composition on a woven or non-woven article, the paste being subsequently foamed.
 7. A process according to claim 1 in which the vinyl chloride polymer is selected from the group consisting of polyvinyl-chloride and copolymers of vinyl chloride with vinylidene chloride, vinyl acetate, vinyl stearate, vinyl propionate, acetyl vinyl ether, tridecyl vinyl ether, ethylene and propylene.
 8. A process according to claim 7 in which said comonomer is present in a minor proportion based on the weight of the copolymer.
 9. A process according to claim 8 in which said comonomer is present in an amount of from 2 to 10 percent based on the weight of the copolymer.
 10. A process according to claim 8 in which said comonomer is present in an amount of from 2 to 5 percent based on the weight of the copolymer.
 11. A process according to claim 1 in which said blowing system is composed of nitrogen-evolving blowing agents.
 12. A process according to claim 11 in which said blowing system is selected from the group consisting of a mixture of azodicarbonamide with benzenesulphonhydrazide or toluenesulphonhydrazide or a mixture of p,p''-oxybisbenzenesulfonylhydrazide with benzenesulphonhydrazide or toluenesulphonhydrazide.
 13. A process according to claim 12 in which said mixture contains from about 10 to about 40 percent by weight of the mixture of azodicarbonamide.
 14. A process according to claim 1 in which said copolymer is fusible at a temperature of from about 135* C. to 150* C.
 15. A process according to claim 1 in which said plasticizer is selected from the group consisting of butylbenzylphthalate, dihexyl phthalate, diheptyl phthalate or dioctyl phthalate.
 16. A process according to claim 1 in which said composition contains a metallic salt or mixtures of metallic salts.
 17. A process according to claim 16 in which said metallic salt is a lead salt.
 18. A process according to claim 17 in which said lead salt is a lead oleate.
 19. A process for producing a textile article backed with vinyl chloride polymer foam fusible at a temperature below about 150* C. which comprises forming a sheet of foamed vinyl chloride polymer from a foamable composition comprising a vinyl chloride polymer, a plasticizer and a nitrogen-evolving blowing system active at a temperature below about 150* C. and fusing said sheet to said article.
 20. A process according to claim 19 in which said article is a carpet. 